Ganymede’s magnetic field

This is a sketch of the magnetic field lines around Ganymede, which are generated in the moon's iron core. Hubble Space Telescope measurements of Ganymede's aurorae, which follow magnetic field lines, suggest that a subsurface saline ocean also influences the behavior of the moon's magnetosphere.

Links:

• NASA press release
• Artist's illustration of aurorae and Ganymede
• Hubble observation of aurorae on Ganymede
• Plot of the rocking of Ganymede's magnetic field
• Cutaway of the Moon Ganymede